Galaxy S20 ultra, june 2023 update. Can't connect to network carrier.

[JoelLoya]

Last night I received the G981USQS5HWF2 security update, and after the installation, my phone can't connect to the carrier network, not for mobile data nor calls.
After doing a factory reset, and changing the SIM with my service provider, it worked for 5 minutes then it went out again.

I'm seriously considering doing a rollback. 

[Buckjunia]

Get your service provider to do a network reset on your phone. Hope this helps

[JoelLoya]

I actually did perform a network reset as well, before doing the factory reset, but to no avail. Now the message I'm getting is that the Sim 1 is not allowed.

Ty for the reply. 
I did try to downgrade but the binary of the latest patch is higher and its incompatible.

[Buckjunia]

Some networks are not working properly for about two weeks. Did you check your service.

[t3chyMr]

Same here. Since the update I can call but no mobile data. Been on phone with EE for 2 hours. They don't know why the phone doesn't attempt to even try connecting. They said it's weird how the call works but the mast says it's not connected for data. Happened after updating.

[Sloly_Pop]

I'm having the same problem its not ok my daughter has been out the country and I could only get hold with her though apps and WiFi this isn't good enough and is a safety issue I feel so let down and out of control to do anything about it as I can't just call someone to Deal with my situation

[Rickwp]

Yep after I do a system update the WiFi calling stops working, I think its time for a apple phone !